The glycosomal ATP-dependent phosphofructokinase of Trypanosoma brucei must have evolved from an ancestral pyrophosphate-dependent enzyme.
Trypanosoma brucei contains an ATP-dependent phosphofructokinase (PFK), located in its glycosomes, which are peroxisome-like organelles sequestering the majority of its glycolytic enzymes. In this paper, we report the cloning and sequencing of the single-copy gene encoding this enzyme. Its amino-acid sequence is more similar to pyrophosphate (PPi)-dependent PFKs than to other ATP-dependent PFKs. A phylogenetic analysis suggests that the enzyme must have been derived from a PPi-dependent ancestral PFK, which changed its phospho-donor specificity during evolution. The enzyme is no longer capable of using PPi as phospho substrate, nor can it catalyze the reverse reaction as PPi-PFKs generally can. Moreover, the presence of a high pyrophosphatase activity in the cell renders it unlikely that PPi can function as free-energy source in present-day trypanosomes. It remains to be determined which mutations were responsible for the change in phospho-substrate specificity of the trypanosomatid PFK. As a result of its particular evolutionary history, the T. brucei PFK shows many structural differences, even at the active site, when compared with other ATP-dependent PFKs. These differences offer great potential for the structure-based design of trypanocidal drugs.
Michels
P A
PA
International Institute of Cellular and Molecular Pathology and Laboratory of Biochemistry, Catholic University of Louvain, Brussels, Belgium. michels@trop.ucl.ac.be
Chevalier
N
N
Opperdoes
F R
FR
Rider
M H
MH
Rigden
D J
DJ
D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites / Q000235:genetics; D003001:Cloning, Molecular; D011756:Diphosphates / Q000494:pharmacology*; D019143:Evolution, Molecular; D005636:Fructosephosphates / Q000378:metabolism; D043564:Inorganic Pyrophosphatase; D008830:Microbodies / Q000201:enzymology; D008969:Molecular Sequence Data; D010732:Phosphofructokinase-1 / Q000737:chemistry* / Q000235:genetics*; D010802:Phylogeny; D011485:Protein Binding; D015800:Protozoan Proteins / Q000235:genetics; D011755:Pyrophosphatases / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship; D014346:Trypanosoma brucei brucei / Q000201:enzymology*
D011756:Diphosphates; D005636:Fructosephosphates; D015800:Protozoan Proteins; C027618:fructose-6-phosphate; D000255:Adenosine Triphosphate; D010732:Phosphofructokinase-1; D011755:Pyrophosphatases; D043564:Inorganic Pyrophosphatase